Electronic circuits may be made from rigid epoxy-metal laminates, using a subtractive process. In such a process, a dielectric is first layered (or laminated) with a solid metal layer, and thereafter, the metal layer is converted to a metal circuit pattern by subtracting away most of the metal. This can result in a fine line conductive circuit pattern. Typically, the metal is removed by chemical etching. However, such processes can be expensive, environmentally unfriendly, and increasingly problematic in meeting performance requirements of the industry.
EP 1 367 872 A2 to Goosey et al. is directed to laser activated dielectric material and an electroless metal deposition process, involving a sensitizing pre-dip and a milling process. The process incorporates titanium dioxide, aluminum nitride or zirconium dioxide filler into a dielectric coating material, and then ultimately converting the filler (using laser energy) into a metallization catalyst.
There remains a need for alternative materials, and processes, for making light-activatable polymer compositions and polymer composites.